1. Field of the Invention
This invention relates to electrical connectors. Specifically, it relates to electrical connectors constructed of a plurality of circuit substrate modules, to which mating terminals and other components may be attached.
2. Brief Description of Prior Developments
Connectors formed of printed circuit boards arranged in side by side relationship have been disclosed. One such system is shown in U.S. Pat. No. 4,521,014. However, the construction shown in this patent would be expensive to produce and difficult to miniaturize.
Published European Patent Application Serial No. 0 752 739 (commonly owned by the assignee of the present invention and incorporated herein by reference) discloses a modular connector system using side by side stacked circuit substrates to form miniaturized, high speed connectors capable of being manufactured at lower cost.
U.S. application Ser. No. 08/784,743 filed Jan. 16, 1997 illustrates modular connectors of a similar type used to form high speed cable interconnections. U.S. patent application Ser. No. 08/784,744 filed Jan. 16, 1997 illustrates arrangements for surface mounting such high speed connectors. Both of these applications are commonly owned by the assignee of the present application and are incorporated herein by reference.
However, a need exists to increase the high frequency performance of these systems and reduce the manufacturing costs. Regarding performance, current widely commercial backplane connector systems having a 2 mm grid pitch run at levels of 10% cross talk at 500 picosecond rise times (0.7 GHz). Electrically enhanced versions of these systems approach a performance level of 6% cross talk at 500 picosecond rise times. However, for data transmission especially performance levels of 1% cross talk at signal rise times of 60 to 100 picoseconds (3.5 to 6 GHz) are desirable for systems meant to carry digital signals at a 2.5 Gigabits/second rate.